Drawing applications like MICROSOFT VISIO enable users to create drawing documents. For example, a user may use a drawing application to add a straight or curved line segment to a drawing document. A user can concatenate such segments to create a more complex shape. Indeed, it is common for predefined shapes provided with a drawing application for users to incorporate in drawing documents in a single step to be defined as a concatenation of segments, also called a “path.”
After a user incorporates such a predefined shape in a drawing document, the user can manipulate it in a variety of ways, such as resizing it in one or both dimensions, attaching text, connectors, or callouts, etc.
Some drawing applications use a spreadsheet engine to perform calculations involved in creating or modifying a drawing document. In particular, a drawing application may represent all or part of a drawing document as one or more spreadsheets comprised of cells each containing a value related to the drawing document.
For example, a drawing application may have a user interface that permits a user to create and place new object instances, such as a predefined shape, or a user-defined shape. In some drawing applications, each object instance created by a user is represented by data stored in one or more spreadsheets. Where a user uses the user interface to modify an existing object instance, the drawing application typically responds by modifying some of the spreadsheet data representing the object, which in turn changes the way that the object instance is subsequently displayed.
Some predefined shapes include special features, such as textual labels or connectors that are aligned relative to a particular point on the shape, such as a vertex of the shape, or in the center of one of the segments that make up the shape. Creating a predefined shape having such special features often involves a significant level of manual effort on the part of the developer. Where such a predefined shape is subject to modifications by the user, such as resizing the shape, changing its aspect ratio, deforming the shape, etc., designing the shape to properly display its special features no matter how it is modified by a user can be particularly difficult.
Further, while it would be desirable to provide such special features for use with user-defined shapes and other user-defined paths, no tools are available that would make it possible to do so.
In view of the above discussion, new functionality for supporting special drawing features for arbitrary paths would have significant utility.